Method and apparatus for making laminated materials



F. LYIJYNEN Nov. 2, 1954 METHOD AND APPARATUS FOR MAKING LAMTNATED MATERIALS Filed June 22, 1951 2 sheets-sheet 1 ".ahg

Nov. 2, 1954 F. L YlJYNEN 2,693,221

METHOD AND APPARATUS FOR MAKING LAMINATED MATERIALS I Filed June 22, 1951v 2 sheets-sheet 2 i f/.////// /////h/ 5' I INVENTOR. 77?/ ggg/7am BY (www,

United States Patent O IVIETHOD AND APPARATUS FOR MAKING vLAMINATED MATERIALS Application June 22,1951, Serial No. 233,026

14 Claims. (Cl. 154-1) This invention relates to the manufacture of laminated upholstery material particularly, although not exclusively, adapted for use as the covering material for vehicle seat and back structures orfor trimming the interiors of vehicle bodies, such as automobile bodies. The laminations of the upholstered material, which preferably include atop or cover sheet of fabric or other ldecorative material, an intermediate layer of padding material and a foundation sheet, are bonded together at predetermined regions between heated'dies by means of a bonding substance which'usually comprises a thermoplastic or thermosetting resinous material. When completely fabricated-foruuse the bonded laminated material is customarily in the form of panels dimensioned for the purposes intended. L

Heretofore, in the fabrication of laminated upholstery panel material or trim panels it has been the practice to cut the sheets or laminations to desired panel size, lay up or assemble the sheets in proper superimposed relation, Yand. introduce the assembled layers or sheets into a hydraulic-press between heated platens which bond the layers together at desired localities under the influence of heat and pressure. Hydraulic presses employed for these purposes are costly and the cost of production consequent to their use is enhanced owing to inactive periods when the presses are open to permit loading thereof and removal of the panels therefrom, also on account of the substantial intervals of time required for carrying out the bonding operations so as to complete the curing or polymerization of the bonding resins used to bond the panel laminations together. In addition, costs of production are relatively high on account of the personnel needed to conduct operations, and the time and handling required to cut the various layers or sheet materials to panel size and assemble them preparatory to introduction into the press.

An object of the present invention is to overcome previous disadvantages encountered in the fabrication of laminated panel materials and to reduce machine, personnel and production costs while at the same time enabling superior laminated articles to be produced for trim yor covering purposes. This object of the invention is accomplished by eliminating individual molding of laminated panels and in lieu thereof molding the laminated materials by a continuous method in which the superimposed panel materials in sheet or strip form are fed between a rotatable die and a fixed or stationary curved die, the former cooperating with the fixed die to compact the laminations at selected regions and to feed the laminations through the machine relatively to the fixed die while in contact with the curved surface thereof. Thus, successive portions of the rotatable die engage-and compress the materials against the curved surface of the fixed die upon entering the machine, each such die portionfmaintaining uniform pressure upon the materials as the latter travel a predetermined distance and for a predetermined period of time in contact with and relatively to the curved surface of the fixed die, whereupon as the materials emerge from between the dies they are bonded together and may thereafter pass through a cutting mechanism effective to cut the laminated sheet or strip into panels.

In the embodiment of the invention herein illustrated, there is provided a die mechanism for bonding together under the influence of heat and pressure and along preice dingsheet and a foundation sheet which, for the purposes of upholstering a seat or back structure, is ilexible or pliable. The machine comprises a fxed or stationary upright die which is concaved to provide a generally arcuate, smooth die surface. A rotatable drum is associated with the stationary die and is mounted upon a shaft driven at the desired speed through suitable drive mechanism. The center of curvature or the curved surface of the stationary die corresponds substantially to the axis of rotation or' the die drum and the latter carry die elements which travel within the cavity yof the stationary die along and proximate to the curved surface thereof. The superimposed laminations of materials in strip form are fed into the machine between the movable die elements and fixed die surface, which successively grip and compact the materials at the selected'regions. 'the materials are fed by the movable die elements against and along the smooth curved die surface of the lixed die during which time the materials are heated to cure or set the bonding substance. The length ot' time that each successive compressed portion of the materials is held in compacted condition under the inuence of heat is determined either by the effective length of the curved I die surface or the speed of revolution or' the die drum or nate corresponding parts in the severalviews.

Fig. l is a transverse sectional elevation, taken substantially through lines 1-1 or' Big. 2, illustrating a machine or apparatus constructed in accordance with one embodiment of the present invention.

Fig. 2 is in part a diagrammatic view and also in part a vertical longitudinal sectional view of the apparatus shown in Fig. 1.

Fig. 3 is a vertical section taken substantially through lines 3--3 of Fig. l looking in the direction of the arrows.

- Fig. 4 is a fragmentary plan view of a strip or sheet of bonded laminated materials after issuingfrom the apparatusshown in Figs. l to 3 inclusive.

Fig. 5 is an enlarged fragmentary sectional view taken substantially through lines 5--5 of Fig. 4 looking in the direction of the arrows.

Before explaining in detail the present invention it is Vto be understood that the invention 1s not limited in its application -to the` details of construction and arrangement of parts illustrated in the accompanying drawings, since the invention is capable of other embodiments and of being practiced or carried out in various ways. Also it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation.

In thefdi'awings there is illustrated, byvway of example, an apparatus for consolidating or bonding together laminations ofsheet or strip material in a continuous manner. This machine or apparatus comprises a base plate or platform 10 which may be mounted upon a suitable upright frame structure or table 11. Rigidly mounted upon the' base 10 is a fixed or stationary die structure 12 which, in the present instance, comprises upper and lower horizontal frame members 12a and 12D, respectively, Which are joined together at the front of the machine by a fixed or stationary heated die member 13. The fixed die member or platen 13 is curvilinear and is of the desired width transversely of the machine so as yto accommodate strip or sheet material of any predetermined width. Although the die member v13 is herein illustrated as being substantially uniform in crosssection thereby providing curved front and rear faces, it will be understood that for the purposes of the present invention it is only of importance that the front face or surface 13a ofthe die be curvilinear so as to provide a stationary generally varcuate pressing surface against which the laminated materials are compacted and bonded together through the medium of travelling die elements carried by a rotatable drum hereinafter described.

The curved die 13 may be heated and maintained at the desired molding temperature by any suitable means, preferably through the usev of steam or by electrical means. In the present instance steam is used to heat the die 13 and maintain it at the required temperature during the molding` or bonding operation. Accordingly, the die or` platen 13 is provided with a suitable number of transverse conduits or steam passages14 extending transversely therethrough. Each passage or conduit is tapped at opposite ends to receive threaded couplings 15 which in turn are connected to piping 16 through which steamis forced under pressure from a suitable source of supply and circulated through the steam passages or conduits in the die orl platen 13.

Rigidly mounted upon the base or platform at opposite ends of the stationary die structure are a pair of similar hollow standards 17. Mounted upon these standards through the medium of .suitable shims 18a are fixed bearing blocks 18 bored to receive bearing bushings 19 within which opposite ends of a shaft 20 are journalled. A hollow drum 21 s keyed to the shaft 2t) for rotation therewith. This drum carries various die elements of predetermined design or configuration for impressing grooves, depressions, indentations or the like in the laminated materials. yIn the present instance, by way of example, the supporting means Yfor the die elements or members comprise bars or blocks rigidly secured to the outer surface of the drum 21 and arranged as desired either transversely of the drum or circumferentially thereof so as to bond the laminated materials together along predetermined lines or regions, such as shown in Fig. 4 hereinafter described.

As an exempliiication of a die structure for eifecting a bond between the laminated materials along lines producing a pattern on the order of that illustrated in Fig. 4, there is rigidly secured, as by welding, to'the outer surface of the drum 21 a number of die supporting bars vor members 22` which project radially of the drum and extend transversely of the machine. Detachably secured in any suitable manner to the outer faces of the bars 22 are die members 23 carrying, in the present instance, pressing elements in the form of ribs 23a. These ribs or die elements, as later described, produce in cooperation with the stationary die 13 spaced parallel transverse grooves in the laminated materials. Whereit is desirable, as illustrated inFig. 4, to form spaced longitudinal grooves or depressions in the materials joined by transverse grooves there may be rigidly secured to the drum an arcuate die supporting plate or block'24 of desired length circumferentially of the drum. Detachably secured in any sm'table manner to the Vcurvilinear die supporting plate 24 is a die member 215 carryingarcuate longitudinal curved pressing elements inthe form of arcuate ribs 25a joined at opposite ends by transverse ribs 25b.

The die elements or ribs carried by .the supporting members 22 and 24 may bey heated in any suitable manner and maintained at the desired temperature for bonding the laminated materials together. In the present instance the die elements are heated electrically through the medium of electrical resistanceeleements` These may be installed either Within the drum 21 or within the die supporting members 22 and 24. In the. present instance the die supporting members are bored to .provide holes or cavities 26 within which are mounted resistance heat,- ing elements 27 each of which is provided with a pair of contact terminals 2S and 29. The contact terminals 28 and 29 project into position to contactand ride over a pair of circular conductor strips or tracks 30 and 31, respectively, which are embedded in andI ,carried by a circular insulating member 32. The latter is boltedat 33 to a `fixed supporting-disk or plate 34 rigidly .secured by means of an angle 35 to the stationary bearing block 18v at the right-hand side of the/machine asy viewed in Fig. 1. Each pair of projecting contact terminals 28 and 29 for the electric resistance elements 27 is encased within an insulating guard or protector'member 36. It will be evident from the foregoing that during rotation of the die drum 21 the contact terminals 28 and .29 wil-l maintain contact with and `ride along the conductor tracksv 3tLand 3,1, and since these tracks are connected infcircuit to a suitable source ofl electricity' the' 'heatingl elements; `27

will be energized thereby to heat the die supporting members 22 and 24.

The shaft 20 and the die drum 21 secured thereto are rotated through the medium of power supplied from a suitable electric motor (not shown) which drives through a sprocket chain 37 a sprocket gear 38. This gear is drivingly connected in any well known manner to reduction gearingmounted Within a casing 39 bolted at 40 to a platform 41. The reduction gearing within the casing 39 drives an output shaft 42 which is connected by a coupling 43 to the drum shaft 20. It will be understood that the reduction gearing `is so selected as to-drive the shaft1 20 and, hence, the die drum 21 at the desired spee It will be .noted .that the vstationary ,die member 13 forms in effect a substantially arcuate cavity within which the drum 21 projectsythe position of this drum and its supporting shaft 20 with relation to the die 13 being such that during rotation of the drum the successive die elements carried thereby move into the concave cavity of the die 13 with the outer working surfaces of the die elements 23a, 25a and 25b travelling in close proximity to the curved or arcuate surface 13a of the die 13. These outer working surfaces of the die elements, as shown in Fig. 3, move along the curved die surface 13a in uniformly spaced relation thereto, the spacing between the die elements and the fixed die surface 13a being predetermined to achieve the proper compacting of the laminated materials, and this spacing may be varied to accommodate different thicknesses of material or variations in the number of laminations in any suitable manner such as by meansof shims which may be introduced between the die members 23 and 2S and the die supporting members 22` and 24.

The upholstery material, which is to be bonded together along predetermined pattern lines or regions, comprises, as illustrated in Figs. 4 and 5, a top cover sheet 44 of cloth or other desired fabric, an intermediate paddingv sheet or layer 45 which may be sponge or `foam rubber, wadding or the like, and a foundation sheet 46. Where the laminated material is to be used for upholstering the seat or back structure the foundation sheet 46 is composed of a flexible or pliable material, such as coarse woven sheeting or other fabric. As illustrated in Fig. 2, the materials or laminations 44, 45 and 46 are preferably fed to the machine in strip formfrom suitably supported rolls 47, 48 and 49, respectively. The top sheet or strip 44 may be fed from the roll 47 through tension guide rolls 50 which are preferably driven by gearing so as to enable these rolls to be driven at variable speeds so as tovary the tautness of the cover sheet as it passes through the machine. The padding layer 4S may be fed from' the roll 48 through tension guide rolls 51and .the foundation layer 46 may be fed from the roll 49 through tension guide rolls 52 over a table 53 and. thence into the machine. The laminations or layers in superimposed relation are fed into the machine .between the rotatable die members and the `fixed or kstationary `die member, and the die elements 23a, 25a and 25b during rotation of the drum 21.successively grip and compact the materials against the smooth arcuate die surface 13a. The die elements embed themselves in the materials and feed them along the xed die surface 13a. After emerging from the upper portion of the die apparatus. as shown in Fig. 2, the laminated material in bonded condition passes over a guide roll V54 and is thence fed rearwardly over the upper horizontal portion 12a of the fixed die 12 to a cutting or shearing mechanism, such as illustrated diagrammatically at 55, which cuts the strip into panels of the desired dimensions.

In Figs. 4 and 5 there is illustrated, by way of .example, a laminated material bonded together along certain pattern lines. It will be understood that these lhave been selected arbitrarily for the purpose `merely of exemplifying a laminated product produced yby va die apparatusv embodying the present invention. As illustrated in Fig. 4, the die member 25 with its die. elements 25a and 25b forms, during each revolution of the drum 21, a seat panel P. This panel is defined bymarginal compressed bondedtogether areas indicated at S6, 57 and 58 which extend continuously around the foursides of the panel. The bonded areas 56 and k58-are formed by the die elements 25b and the areas 57 are formed by two of the die elements 25a located at opposite `ends of the die ,plate 25. The -panel P isz :bonded: together areas 63.

materials along the lines 5659, they are compressed grausamy along parallel pattern lines 59 joining the areas 56 and 58, these being formed by arcuate die elements or ribs 25a carried by the die plate 25. When thefsuccessive panels P, formed in the laminated material, pass through the cutting or shearing mechanism 55, they are cut out or separated from the laminated stripy along the outer marginal lines 61 bounding the bonded areas 56, 57 and S8. Since these areas are hat and compressed they provide a convenient means for stitching the upholstered seat cover P to the trim fabric covering the upright sides, front and back of the seat. It will be seen that by compressing or bonding theA materials forming the panel P along the narrow parallel lines 59, there are provided intervening uncompressed padded areas 60. VAs also illustrated in Figs. 4 and 5, the laminated strip, as it is fed through the machine, is compressed and bonded together by the die elements 23a along transverse lines 62, these die elements producing Vrelatively deep grooves along these lines and intervening uncompressed padded It will be understood that in bonding the together in a manner generally similar to thatillustrated at 62 in Fig.- 5.

Although in the present embodiment the die apparatus is illustrated for thepurpose of producing flexible or pliable upholstery panels especially useful as coverings for back and seat structures, it will be` understood that the invention may be used for the purpose of fabricating relatively stiff trim panels such as are used in trimming the insides of automobile doors. For such purposes the foundation layer may comprise a comparatively stii material such as iiberboard. Such material, however, will be sufficiently bendable so that it may be fed through the machine in conjunction with the padding l and cover sheets. In order to reduce to a minimum the amount of bend to which the foundation board would be subjected to when fed along the curved die surface 13a, this surface as Well as the diameter of the drum 21 may be relatively great.

The bonding substance for bonding together thelaminations may be applied either to the surface of the foundation sheet 46 or the surface of the padding layer 45 or both and is usually somewhat tacky and of a kind that will be cured or polymerized under the inuence of the heat from the die member 13 and the rotatable die elements which cooperate therewith. Such bonding substance preferably includes, at least in part, a thermosetting resin such as a phenol-formaldehyde resin or a urea formaldehyde resin which is in an intermediate stage of reaction when applied to the laminations and which will cure or set permanently under the influence of heat upon being subjected thereto during a predetermined period of time. In connection withl upholstery panels for seat'and back covers it is desirable that the bonding substance be such as not only to permanently bond the laminations together but also to provide bonded lines or areas which are flexible or pliable. T hisvis important in connection with seat or back cushions which are subjected to deforming or distorting forces due to the weight of the occupant of the seat. It has beenfound that thermosetting resins, especially of the phenolic type, when used as the bonding medium produce undesirably sti bonding lines or regions which are comparatively brittle and, when deformed or bent out of shape due to the weight of the occupant of the seat, crack or pucker and eventually produce an unsightly appearance along the bonding pattern lines.

I have found that relatively flexible or pliable bonding lines or regions may be produced by means of a bonding resin comprising as the principal constituents thereof atrubber-like bonding substance mixed with a phenolic resin. As an example, a rubbercement cornposed principally of approximately three parts of a synthetic or natural ,rubber or latex and one part of rosin or colophony may be utilized. A liquid varnish may be prepared by mixing this cement and a phenolic resin in a water carrier, the cement and resin being of the types that are soluble or miscible in water. This resin mixture may comprise, for example, from approximately 5% to 11% by weight of phenolic resin and from approximately 22% to 28% by weight of Vrubber cement, the balance ofthe varnish being water. Such a bonding mixture, when cureduuder heat and pressure, will produce exible or pliable bonding lines or areas and will withstand the bending or deforming forces to which the seat or vback cushion issubjected to on account of the weight t of they occupant.

I claimz. l. ln-a die apparatus for bonding together laminated materials through the medium of a bonding material said materials including a backing sheet, a cover sheet and an intermediate Ypadding sheet; a xed die member formed with a concave recess providing a smooth plain curved die surface, a rotatable die member, die elements carried thereby and movable during rotation of the rotatable die member along and proximate to said curved die surface, and means for rotating said die member to cause said die elements to successively engage and embed in said cover and padding sheets at spaced localities and to compactthe same at said localities against said backing sheet and curved die surface and feed the sheets relatively to and along said surface to bond the same together at said localities. f

2. In a die apparatus for bonding together laminated materials through the medium of a bonding material,

said materials including a backing sheet, a cover sheet` and an intermediate padding sheet; a xed die member formed with a concave recess providing a smooth plain curved die surface, a rotatable die member, die elements` carried thereby and movable during rotation of the rotatable die member along and proximate to said curved die surface, means forheating said die elements, and means for rotating said die member to cause said die elements to successively engage and embed in said cover and padding sheets at spaced localities and to compact the same at said localities against said backing sheet and curved die surface and feed the sheets relatively to and along said surface to bond the same togetherat said localities.

3. In a die apparatus for bonding together laminated materials through the medium of a bonding material, said materials including a backing sheet, a cover sheet and an intermediate padding sheet; a fixed die member formed with av concave recess providing a smooth plain curved die surface, a rotatable die member, die elements carried thereby and movable during rotation of the rotatable die member along and proximate to said curved die surface, and means for rotating said die member to cause said die elements to successively engage and embed in 4. In a die apparatus for bonding together laminated materials including a backing sheet, a cover sheet and an intermediate padding sheet; a xed die member formed with a concave recess providing a smooth curved die surface, a rotatable die member, die elements carried thereby and movable during rotation of the rotatable die member within said recess along and proximate to said curved die surface and spaced therefrom a less distance than the thickness of said materials, means for rotating said die member to cause said die elements to successively engage and embed in said cover and padding sheets to compact the same at spaced localities against said backing sheet and curved die surface and feed the sheets relatively to and along said surface to bond the same together at said localities, and means for heating said sheets while in contact with said die surface.

5. In a die apparatus for bonding together laminated sheets through the medium of a bonding material introduced between adjacent sheetsz a fixed die member formed with a concave recess providlng'a plain curved die surface, a rotatable die member, die elements carried therel by and movable during rotation of the rotatable die member within said recess along and proximate to said curvedtion yof said rotatable die member and said die elements being spaced from said die surface a less distance than the combined thickness of said sheets, and means for heating said sheets while in contact with said die surface.

geesten-11i- 6.; An die; apparatus: for.; bondngi'itogetherlaminationsi of material through the rnediumfoffa--bondingsubstance; comprising a die member having a xed generallwarcuate diedsurface, a:.rotatable. drum, die elements -mounted .on the r outer. face of said drum;

adjacent said die :member to.i.causeieachf diefelement f during. -rotationn of the drum.. to wmoven into position tof compact. said .laminations latt-.spaeedf'localities againstnsaidfl die surface adjacent vone end thereof andto Imaintailiv'saids laminations` ini .compacted .relation `against :saidfdiefsurfacef- 10: i

to bond the .same together :at-'said ;localities las feachbsuchf: die element travels along-said sunfacerto:agpointladjacentf the opposite zend., thereof, said ldiev elements bein'gcsplaced',` from said ldie; surface al less distanceA 1t1i\an,^.the.` combinedil thickness a of 1 saidlaminationsf each,` die elements: at saidd 151 1 latterl i end moving 1 away from.` said dief surfaee'stoareleasei4 said laminations, and. means fomheating said laminations 1 during the travel thereof along saidtdies-sunfcet:

7. Ardie apparatusfor-bondingwtogether ythrough the medium' of g aibonding substanceya :backi-ngisheetn and: :a:. pluralityv of Acover sheets y:superi1r1p-osed thereon; compris-'.1 ing 1.a:.ixed.:.upright die. memberfhavingta;irecessfterminati ing in atfront openingiand havingv'az.'cunvedrlback..Walla formingia plainadie :surface,. arotatablerdnum; die means;` mounted.y upon the outery side of `said drunr, .meansa for mounting: saidz.- drumi adjacent rsaid opening: to-.ipositionf portions of said .diet means:y within.'.saidfrecessawithf.thea: outerV surfaces :thereof proximateto: saididie surface: sox: asttoembed in saidifcoverfsheetsfat spaced localitiesand press `thesame .against said backing sheet. andrd-iessurfacei. and vbond. .the same together, and means:for-rotatingsaidf, drurnnto cause successive vportionsioff'saidndie :means tof.v4 enga'gessaid1-laminations adjacent onejendeof said'zopeningg-. feed the.` same :in compacted conditionalong saiddie surface,IA and release the. samefatthe oppositeeend tofisaid;` openings 8u A dier; apparatus for bonding` i together a laminations .1.- of: material.. through :thefmedium of.v a-'bondingasubstancc-,t comprising a. fixed upright die memberfy havingca.L recesS1. terminating :in a vfront openingv and'having a1 curved:bacia:V wall forming a :plain s die surface,. a frotatable:drum;l die' means mounted upon. the outer side :of saidudrum; means: for; mounting .said .drum adjacent Asaid opening :tocpositiona` portions ofsaid die means withinzsaid recess with thefouter. surfaces thereof proximate-towsaid :die surfaces-.soz-asito compact -said laminations against vsaidnsunfaceiandabondu the same/together,l means for rotatingrsaidadrumwto cause successive portions off'said die means =to engage said lami-.- nations adjacent sone end ofi-:said opening,v feed the-samaA in compactedl conditionalong said die'surface, andfrelease the.L same-at. :the oppositeend of. said. opening, andameans` for heating said laminations during the trailelxthereof.V alongsaid .die surface, said diey means being spacedufrom said die. surface 1 a less distancef than the; cox1tbin`ed;,thi :k nessrofsaid laminations.

9.1'AYA die `apparatus v.for bondinggtogethernlaminationsf. of-:material through1the mediumof sa bonding.esubstanteav comprising a: fixed upright :die: member."'havingtazfrecess terminating in a front-opening and-havingaacurvedrback'f. wallr forminga plain diesurface, a:rotatablevdrum', die; means mounted. upon zthe outer .sidefo .said:.clrum,f mcanss. for 3 mounting saidadrum adjacent :saidopeningnto. ,posifi tion=-portions of said :die means. within'said;recesstwithnA theoutensurfacesthereof proximateato saiddie surfaces so as .to compact-said laminationsagainst. said-.surface f andbon'd the-same together, means *for-rotatingsaiddrumn to .cause successive portions of said die'means'toengage.y said laminations adjacent one endv of .saitkopening'l feed the samefin compacted condition along said idie surface, and release thesame at the opposite end of said..opening,; said die surface throughout themajor. length thereof being y arcuate with the center of .curvature ,thereof substantiallyA at the axis of ,rotation of thedrum, andl means for. heating.-v said. laminations during. thetravelv thereof along saiddie surface.,4 said. die ,means being, spaced. from 4 said .die sur. face'aless `distance than the .combined thickness of saidv. laminations.

10., In a die apparatus for bondingtogetherlaminated; materials through the mediumof a .bonding.,substance said materials including a backing;l sheet, a cover sheet and ,an .intermediate padding sheet; a. fixed upright die. member having yagenerally arcuate plaindie surface, ai rotatable drum, a curveddie supporting,member, secured means` for .1 mounting: #said1 5f! heatftofsaidsheetsat said L rotatable sheets 'at spaced localities and to rotatablendrum,x 'dieY tof,- thee outer surface ofsaid difum" andl havin-gM spacedtransverselyextending rib-like die elements.and longitudi-l nally extending 1 curved rib-likel .L die elements-extending b'etweenfsaidrst named die-elements, meansfor support ingfand rotating saiddrum Ato Vmove said die elements to embed the same-in1said1cover1and padding -sheets acipredetermined areas andpress thesame-against said backing sheet and 'die' surfacel at said lareas `and -to feedthe materials-along1 and# relativelyto saidldie surface during aL portion: oi'-l one revolution of the drum, said die elements during .another portion of 5one revolution i of the drum i moving-away from isaid -die 1 surfaceA toy release the. materials; and rneansfor.heating` the materials-while-'under compressionbetween-said die elements .Land die surface.

11'. Theumethod'ofv bondingy togethcrlaminated materials Jincludngoa covcrfsheet and an underlying padding" sheet, including the 1steps -of 1 introducing said materials betweenl. a. stationary `curved"substantiallyfplain dieA surface-fand @dier` elements finterposedbet-weenI said materials and'rotating said drum'to feed saidl materialsralongandllrelat-ive-to `said die surfacel and'fto" cause f said 1 die` Yelements I to travel with' xsaid materials' and i to embed in said cover and padding sheetslatfispacedrlo calitiesragainstsaid-1diefsurfaceandf at-the same' time bonding said sheetsi together :at said '-localities.

12.,.1n a die -apparat'usfor bonding. togetherflaminated materials throughthefmedium'ofa bonding material, said'A materlals includingia cover-sheet'andan underlying-pad-'- dmgfsheety a stationaryfdiefmembereconcaved'-to provide smoothv plain-cu1'ved"diel surface,- aA rotatable. drum, dlevelements l.adaptedv tol be interposed f betu/eenusaidtdrumwandesheets and movable therewith* during :rotation-'ofthe drum-along andfproximateto said curveddiesurface; and means -forfrotating said vdrum to forceasaidzdieelementstoembedfiin Asaid cover and padding-sheetszab spaced-localities andto compact the same atvsaid. .localities Vagai-nst said'curved-die surface and to feed rtheasheets relativelyto=and alongy said surface to' bond the saine together at said localities.

13. In `a d1e^apparatus for `bonding-together''laminated materials through the medium -of a'bonding material, said4 materialsmcluding alcover Asheet-and an underlying pad' ding. sheet, avstationary 4diemember concavedto Aprovide ac-.recess'having a: smoothl plain-,curved die surface, a

rdimm, die-elements adapted'to/ be interposedy betvveenl ,said drum` andlsheetsy and 'movable therewith durmg rotation; ofvthedrum along and-proxir'nateto said curved dieisurface,-fmeans iforl rotating saidl drum to force said dle.- elements to :embed v'inl said :cover "andpadding u compact the sameat'said localities against: saiddcurved die-surfacey and' to -feed-fthe sheets'rrelatively to ."andalong Asaid surfacedofbond the sameatogetherr at- :saidf-localities;l and means for applying .v localities; y A 14.1In`y a die) apparatus` for bonding-together laminated i materialsy through the Imedium 'of afbondingmaterial,z said4 matcrialsnncluding acoverzsheet andfanA underlyingpadl ding sheet; a stat1onary-diemember 'concavedzto provide' anrecess 1havunggaA smooth; plain-curved fdie surface, a elements adapted'y to be'intcrposed" betvyeen said `drumhandl sheets andy movabler therewith during ynatation. of the drum-along and proximate torsaid curved'dle surface,-` and means for yrotating .said vdrum t0 force ysaid'dlerelements toembed in saidr cover and 'padding :sheets at spacedl ylocalities and to `compact the same at said-localities-agamst saidscurved die*` surface and to feed the sheets relatively to and along said surface to bond the .same together atsaidflocalities,l said `die elements having sheetembedding `portionslspacedffrom saddie surfacefazless distance-than thefthickness of' said materials durlng .operation ofthe4 die elements to compact said. materials, atsaid localities.:

References. Cited l`in the 4le .of vthis patenti UNITED "STATES PATENTS Number 

